monsoon question
Many including myself go with the Alpine SPS170a to replace the factory door speakers. Much better sound out of them and they won't blow after only a few weeks like the stock replacements.
The rears are a different story and from what I've heard, and don't really do much on a convert in terms of providing substantial sound improvement. So unless they're blown don't bother.
There are complete systems which blow away the above speaker swap only option, but all depends on $$ you want to drop.

